A computerized axial tomography scan is commonly known as a CAT scan or CT scan. The CT scanning machine uses X-rays to make detailed pictures of various structures inside of a patient's body. The CT machine looks like a giant doughnut having a central opening and being tipped on its side. The machine includes a plastic case or covering that protects the internal workings of the machine. Typically, this case is provided in two halves on opposite sides of the central opening. An X-ray tube is mounted on a movable ring around the edges of the central opening. The ring also supports an array of X-ray detectors arranged directly opposite the X-ray tube. A motor turns the ring so that the X-ray tube and the X-ray detectors revolve around the body. Each full revolution of the ring causes the X-ray tube and the X-ray detectors to scan a narrow, horizontal “slice” of the body. A clear plastic or Mylar covering, referred to hereinafter as a “window”, protects the movable ring and it associated parts and is arranged between two halves of the plastic case. The window is located between two metallic rings that are arranged between the halves of the case and is removable. The flexible, removable window is situated between the two halves of the CT scanner and is designed to prevent moisture damage and body fluid contamination to the internal components of the CT unit. In some CT scanners, the window which allows the emission of coned X-ray beams may comprise plastic or other substances.
A table or platform is associated with the CT machine and slowly moves through the hole in the machine as the patient rests thereon. The control system moves the platform farther into the hole so that the tube and detectors can scan the next slice of the patient's body. During a CAT scan, a patient lies on the table while pictures of the internal structure being viewed are generated. The CT scanner sends X-ray pulses through the body area being studied. Each pulse lasts less than a second and takes a picture of a thin slice of the area of the body. The X-ray pictures are saved on a computer and combined with the aid of a computer to generate cross-sectional views and three-dimensional images the patient's organs and body structures. A CAT scan is used to define normal and abnormal structures in the body and/or assist in procedures by helping to accurately guide the placement of instruments or treatments.
In each of the pictures created during the CAT scan, the body is seen as an X-ray slice of the body, which may be recorded on film, as a digital image for viewing on computer monitors or preserved on other electronic storage media. This recorded image is called a tomogram. “Computerized Axial Tomography” refers to the recorded tomogram “sections” at different levels of the body. The body is seen on CAT scan slices in a similar fashion from the skin to the central part of the body being examined. When these levels are further “added” together, a three-dimensional picture of an organ or abnormal body structure can be obtained.
During the CT process, patients are often given an oral or intravenous dye that acts as a contrast material to aid in the evaluation of a patient and optimize the performance of the machine. This contrast material is very sticky which creates difficulty in cleaning it up after a spill has occurred during the examination process. Moreover, this material may cause the patient to become nauseous and regurgitate which tends to soil the machine. In fact, patients who require CT scans are often sick, injured, or may become ill during the process resulting in body fluids, or like substances, from the patient being dispersed onto the CT machine. Since the plastic casing and the window are not integrally sealed together, there exist two unsealed seams on opposite sides of the window into which contrast materials, body fluids or like substances may seep. Thus, these fluids may enter either of these seams and render the machine inoperable or contaminate the inner workings of the machine with body fluids.